_dummy_thread — Drop-in replacement for the _thread module — Python documentation
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Python/docs/3.8/library/ dummy thread
_dummy_thread — Drop-in replacement for the _thread module
Source code: :source:`Lib/_dummy_thread.py`
Deprecated since version 3.7: Python now always has threading enabled. Please use _thread (or, better, threading) instead.
This module provides a duplicate interface to the _thread module. It was meant to be imported when the _thread module was not provided on a platform.
Be careful to not use this module where deadlock might occur from a thread being created that blocks waiting for another thread to be created. This often occurs with blocking I/O.